Question 1

In humans, the embryonic and fetal forms of hemoglobin have a higher affinity for oxygen than that of adults. This is due to

Accepted Answer

A)  nonidentical genes that produce different versions of globins during development. 
B)  identical genes that generate many copies of the ribosomes needed for fetal globin production. 
C)  pseudogenes, which interfere with gene expression in adults. 
D)  the attachment of methyl groups to cytosine following birth, which changes the type of hemoglobin produced. 
E)  histone proteins changing shape during embryonic development. 
A)  nonidentical genes that produce different versions of globins during development. 
B)  identical genes that generate many copies of the ribosomes needed for fetal globin production. 
C)  pseudogenes, which interfere with gene expression in adults. 
D)  the attachment of methyl groups to cytosine following birth, which changes the type of hemoglobin produced. 
E)  histone proteins changing shape during embryonic development.

Question 2

Use the following information to help you answer the next few questions.
Multigene families include two or more nearly identical genes or genes sharing nearly identical sequences. A classical example is the set of genes for globin molecules, including genes on human chromosomes 11 and 16.
-How might identical and obviously duplicated gene sequences have gotten from one chromosome to another?

Accepted Answer

A)  by normal meiotic recombination 
B)  by normal mitotic recombination between sister chromatids 
C)  by transcription followed by recombination 
D)  by chromosomal translocation 
E)  by deletion followed by insertion 
A)  by normal meiotic recombination 
B)  by normal mitotic recombination between sister chromatids 
C)  by transcription followed by recombination 
D)  by chromosomal translocation 
E)  by deletion followed by insertion

Question 3

Which of the following is a representation of gene density?

Accepted Answer

A)  Humans have 2,900 Mb per genome. 
B)  C. elegans has ~20,000 genes. 
C)  Humans have ~20,000 genes in 2,900 Mb. 
D)  Humans have 27,000 bp in introns. 
E)  Fritillaria has a genome 40 times the size of a human genome. 
A)  Humans have 2,900 Mb per genome. 
B)  C. elegans has ~20,000 genes. 
C)  Humans have ~20,000 genes in 2,900 Mb. 
D)  Humans have 27,000 bp in introns. 
E)  Fritillaria has a genome 40 times the size of a human genome.

Question 4

Why might the cricket genome have 11 times as many base pairs as that of Drosophila melanogaster?

Accepted Answer

A)  The two insect species evolved in very different geologic eras. 
B)  Crickets have higher gene density. 
C)  Drosophila are more complex organisms. 
D)  Crickets must have more noncoding DNA. 
E)  Crickets must make many more proteins. 
A)  The two insect species evolved in very different geologic eras. 
B)  Crickets have higher gene density. 
C)  Drosophila are more complex organisms. 
D)  Crickets must have more noncoding DNA. 
E)  Crickets must make many more proteins.

Question 5

The comparison between the number of human genes and those of other animal species has led to many conclusions, including that

Accepted Answer

A)  the density of the human genome is far higher than in most other animals. 
B)  the number of proteins expressed by the human genome is far more than the number of its genes. 
C)  most human DNA consists of genes for protein, tRNA, rRNA, and miRNA. 
D)  the genomes of other organisms are significantly smaller than the human genome. 
A)  the density of the human genome is far higher than in most other animals. 
B)  the number of proteins expressed by the human genome is far more than the number of its genes. 
C)  most human DNA consists of genes for protein, tRNA, rRNA, and miRNA. 
D)  the genomes of other organisms are significantly smaller than the human genome.

Question 6

Use Figure 18.1 to answer the next few questions.
   Figure 18.1
Types of DNA sequences in the human genome.
The pie chart in Figure 18.1 represents the relative frequencies of the following in the human genome:
I. repetitive DNA unrelated to transposons
II. repetitive DNA that includes transposons
III. unique noncoding DNA
IV. introns and regulatory sequences
V. exons
-Which region includes Alu elements and LI sequences?

Accepted Answer

A)  A 
B)  B 
C)  C 
D)  D 
E)  E 
A)  A 
B)  B 
C)  C 
D)  D 
E)  E

Question 7

In order to determine the probable function of a particular sequence of DNA in humans, what might be the most reasonable approach?

Accepted Answer

A)  Prepare a knockout mouse without a copy of this sequence and examine the mouse phenotype. 
B)  Genetically engineer a mouse with a copy of this sequence and examine its phenotype. 
C)  Look for a reasonably identical sequence in another species, prepare a knockout of this sequence in that species, and look for the consequences. 
D)  Prepare a genetically engineered bacterial culture with the sequence inserted and assess which new protein is synthesized. 
E)  Mate two individuals heterozygous for the normal and mutated sequences. 
A)  Prepare a knockout mouse without a copy of this sequence and examine the mouse phenotype. 
B)  Genetically engineer a mouse with a copy of this sequence and examine its phenotype. 
C)  Look for a reasonably identical sequence in another species, prepare a knockout of this sequence in that species, and look for the consequences. 
D)  Prepare a genetically engineered bacterial culture with the sequence inserted and assess which new protein is synthesized. 
E)  Mate two individuals heterozygous for the normal and mutated sequences.

Question 8

Use Figure 18.2 to answer the next few questions.
   Figure 18.2 shows a diagram of blocks of genes on human chromosome 16 and the locations of blocks of similar genes on four chromosomes of the mouse.
-Which of the following represents another example of the same phenomenon as that shown in Figure 18.2?

Accepted Answer

A)  the apparent centric fusion between two chromosome pairs of primates such as chimps to form the ancestor of human chromosome 2 
B)  the difference in the numbers of chromosomes in five species of one genus of birds 
C)  the formation of several pseudogenes in the globin gene family subsequent to human divergence from other primates 
D)  the high frequency of polyploidy in many species of angiosperms 
A)  the apparent centric fusion between two chromosome pairs of primates such as chimps to form the ancestor of human chromosome 2 
B)  the difference in the numbers of chromosomes in five species of one genus of birds 
C)  the formation of several pseudogenes in the globin gene family subsequent to human divergence from other primates 
D)  the high frequency of polyploidy in many species of angiosperms

Question 9

Two eukaryotic proteins are identical except for one domain in each protein, and these two domains are completely different from each other. Which of the following processes is most likely to have contributed to this difference?

Accepted Answer

A)  gene duplication 
B)  alternative splicing 
C)  exon shuffling 
D)  histone modification 
E)  random point mutations 
A)  gene duplication 
B)  alternative splicing 
C)  exon shuffling 
D)  histone modification 
E)  random point mutations

Question 10

Bioinformatics includes all of the following except

Accepted Answer

A)  using computer programs to align DNA sequences. 
B)  analyzing protein interactions in a species. 
C)  using molecular biology to combine DNA from two different sources in a test tube. 
D)  developing computer-based tools for genome analysis. 
E)  using mathematical tools to make sense of biological systems. 
A)  using computer programs to align DNA sequences. 
B)  analyzing protein interactions in a species. 
C)  using molecular biology to combine DNA from two different sources in a test tube. 
D)  developing computer-based tools for genome analysis. 
E)  using mathematical tools to make sense of biological systems.

Question 11

Use Figure 18.1 to answer the next few questions.
   Figure 18.1
Types of DNA sequences in the human genome.
The pie chart in Figure 18.1 represents the relative frequencies of the following in the human genome:
I. repetitive DNA unrelated to transposons
II. repetitive DNA that includes transposons
III. unique noncoding DNA
IV. introns and regulatory sequences
V. exons
-Which region is occupied by exons only (V)?

Accepted Answer

A)  A 
B)  B 
C)  C 
D)  D 
E)  E 
A)  A 
B)  B 
C)  C 
D)  D 
E)  E

Exam 18: Genomes and Their Evolution

In humans, the embryonic and fetal forms of hemoglobin have a higher affinity for oxygen than that of adults. This is due to

Which of the following is a representation of gene density?

Why might the cricket genome have 11 times as many base pairs as that of Drosophila melanogaster?

The comparison between the number of human genes and those of other animal species has led to many conclusions, including that

In order to determine the probable function of a particular sequence of DNA in humans, what might be the most reasonable approach?

Two eukaryotic proteins are identical except for one domain in each protein, and these two domains are completely different from each other. Which of the following processes is most likely to have contributed to this difference?

Bioinformatics includes all of the following except

Introduction: Evolution and the Foundations of Biology

The Chemical Context of Life

Carbon and the Molecular Diversity of Life

A Tour of the Cell

Membrane Transport and Cell Signaling

An Introduction to Metabolism

Cellular Respiration and Fermentation

Photosynthesis

The Cell Cycle

Meiosis and Sexual Life Cycles

Mendel and the Gene Idea

The Chromosomal Basis of Inheritance

The Molecular Basis of Inheritance

Gene Expression: From Gene to Protein

Regulation of Gene Expression

Development, Stem Cells, and Cancer

Viruses

Descent With Modification

Phylogeny

The Evolution of Populations

The Origin of Species

Broad Patterns of Evolution

Early Life and the Diversification of Prokaryotes

The Origin and Diversification of Eukaryotes

The Colonization of Land by Plants and Fungi

The Rise of Animal Diversity

Plant Structure and Growth

Resource Acquisition, Nutrition, and Transport in Vascular Plants

Reproduction and Domestication of Flowering Plants

Plant Responses to Internal and External Signals

Homeostasis and Endocrine Signaling

Animal Nutrition

Circulation and Gas Exchange

The Immune System

Reproduction and Development

Neurons, Synapses, and Signaling

Nervous and Sensory Systems

Motor Mechanisms and Behavior

Population Ecology and the Distribution of Organisms

Species Interactions

Ecosystems and Energy

Global Ecology and Conservation Biology

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